Henck,A.C., Huntington,K.W., Stone,J.O., Montgomery,D.R. and Hallet,B.(2011): Spatial controls on erosion in the Three Rivers Region, southeastern Tibet and southeastern China. Earth and Planetary Science Letters, 303, 71-83.

『南東チベットと南東中国の三河川地域における浸食に対する空間コントロール』


Abstract
 Global data suggest that erosion rates variously scale with steepness or climate forcing (precipitation or glacial excavation), but the relative influence of these factors has proven difficult to assess without comparisons from a single location. A new suite of detrital 10Be data from the Three Rivers Region, SE Tibet is used to examine the relative importance of rainfall and relief in predicting patterns of erosion rates across a region with a strong gradient in exhumation. The data reveal millennial erosion rates vary by two orders of magnitude, from 0.01 to 8 mm/yr across a regional gradient in exhumation rates inferred from previous thermochronology and cosmogenic nuclide data to the west and east of the study region. The new millennial erosion rates mirror the pattern of decreasing exhumation rates from west to east across the region, with the highest rates in the lower Salween River drainage and the lowest rates in the Yangtze River drainage. Erosion rates in the Mekong and Salween River drainages are correlated with mean local relief whereas in the Yangtze River drainage they are correlated most strongly with mean annual rainfall. The tectonic setting of this region, with a strong west to east gradient in exhumation rates which we infer to mirror a gradient in rock uplift, seems to exert a stronger control on erosion rate patterns than rainfall or relief.

Keywords: Three Rivers Region; basin wide erosion rates; tectonic geomorphology; China; Eastern Tibet』

1. Introduction
 1.1. Tectonic setting and exhumation in the TRR
2. Methods
 2.1. Erosion rates from 10Be
 2.2. Potential indicators of erosion
  2.2.1. Steepness - predicting erosion rate patterns using mean local relief
  2.2.2. Climate - predicting erosion rates from mean annual rainfall
3. Results
 3.1. Erosion rates from Be-10
 3.2. Patterns of local relief and mean annual precipitation
4. Discussion
 4.1. Potential influence of lithology and differential river incision on measured erosion rates
 4.2. Relief and rainfall as indicators of erosion rates
 4.3. Geomorphic mechanisms potentially controlling TRR erosion rates
5. Conclusions
Acknowledgements
Appendix A. Supplementary data
References


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